Safety device.



C. F. ROOT.

SAFETY DEVICE.

APPLICATION FILED AUG-17. I914- 1,298,566., Patented Mar. 25,1919.

3 SHEETS-SHEET I.

C F ROOT SAFETY DEVICE. APPLICATION FILED AUG. I7. 1914.

Patented Mar. 25, 1919.

3 SHEETSSHEET 2.

C. F. ROOT.

SAFETY DEVICE.

APPLICAIION FILED AUG. 17. 1914.

1,298,566. Patented Mar. 25,1919.

F 5 3 $HEET$-SHEET 3.

' @KWUZW I I FI-Q 33,13 5

' Gum/M1 sary for the operator of the machine to per-' warren snares PATENT @FFKQE. v

CHARLES F. ROOT, 0F RAVENNA, OHIO, ASSIGNOR Olv ONE-FOURTH TO BYRON O. CONN,

OF MANSFIELD, OHIO.

SAFETY DEVICE.

. as for example a punching press.

The object of my invention is to rovide means for automatically rendering t e link that imparts movement to, the reciprocating work engaging element inoperative when an obstruction is inadvertently or otherwise placed between the element and the anvil and upon engagement of the element with the obstruction.

It is well known in the operation of machines that are provided with a reciprocat ing work engaglng element which exerts a pressure upon an anvil, die or the like, that there is great danger of the operators fingers being inadvertently placed between the anvil or die and the reciprocating element that exerts pressure to perform the work, with the result that the fingers are crushed or injured.

This is especially true when it is necesform work that requires him to place his hands in close proximity to the anvil or die of the machine, and in manipulating the work his hand is liable to be engaged by the reciprocating working element at the time the latter is about to perform its work. I

The primary object, therefore, of my invention is to provide means of relieving the pressure that i exerted by the reciprocating element upon the anvil or die to perform the Work when an obstruction is interposed be-.

tween the anvil or die and the reciprocating element.

Theinvention more specifically consists in the combination of a link and pawl which are adapted to impart movement to the reciprocating work engaging element, the pawl being automatically actuated to inter- Specification of Letters Patent.

lock with the link to provide means for connecting the work engaging element and the driving means whereby to positively operate the work engaging element just prior to and during the time it is performing its work and further to, provide automatic means for positivelymaintaining the pawl released or unlocked with relation to the link during the major portion of the work- 1ng stroke of the reciprocating work engaging element.

The link and pawl are preferably constructed and actuated to interlock to positively actuate the work engaging element when the latter is about% of an inch above the end of its downward stroke, so that if an obstruction, larger than of an inch is interposed or inadvertently placed between the Work engaging element and anvil no pressure will be exerted upon .the obstruc- 'tion or anvil except the weight of the work Patented Mar. 25, 1919.

Application filed August 17, 1914. Serial No'. 857,016.

A further object of the invention is to i provide a safety device which canbe applied to machines of the class described without altering or modifying [the latter to any material extent. 1 I

' The above .and other objects are attained by the mechanism illustrated in the accompanying drawings, in which:

Figure 1 is a front elevation of a conventional type of staying machine showing the invention applied thereto, and also showing the finger o the operator interposed between the anvil and the reciprocating work engag ing element; Fig. 2 isa detail view, in rear elevation of the link and pawl looking from the rear toward the front of the staying machine showing the pawl interlocked with the 'link in full lines and released therefrom in dotted lines;

Fig. 3 is a side view partly in section, (of the link and pawl; i

Fig. 4 is a view similar to Fig. 3, of the opposite side of the link and pawl;

Fig. 5 is a side elevation, partly in section of Fig. 1 on a reduced scale;

Fig. 6 is a front elevat'on of the cam- Inthe drawings the driving shaft 1, is provided with a disk 2 having a crankarm 3, the shaft being journaled in suitable bearings provided in-the L-shaped arm 4, of a conventional type of staying, machine.

Movement is imparted to the driving shaft 1 by'the driving ulley 5. A head 6 reciprocates between t e ways 7 and shaft 8 secured thereto.

f The face 9- of the free end ofthe L-shaped has .a stud arm 4" is countenbored providing a space '10 surrounding the disk 2 into which space a cam holder 11 is inserted, the latter, having an aperture therein to receive the disk 2. The cam holder is held in place by screws. 12 vwhich pass through apertures 13' and 14 and are threadably engaged with threaded apertures formed in the head. Two cams 15 and 16 are arranged at spaced points on the outer faceof the cam holder and are securedxtheretoin any suitable manner.

The follower or work engaging element 17 is securely attached to the-head 6 and 00-- operates with the usual anvil 18 of a staying machine. I For the purpose of connecting the stud shaft 8 of the head. to the crank .3-'of thedfiving shaft 1 by means of'which reciproeating movement is imparted. to the head 6 link 19 .which-is'adapted to be interlocked7 v with and released from a pawl'20 is pro-' vided. The 'link 19 is cut away or reduced on one side thereof at'21,-forming a sho u1- der or abutment 22 which is adapted'to contact with the free lower end-23 of the pawl. 'A bearing or bushing 24 is secured to the f upperend of the pawl and has one end thereof slidably projecting-into an oblong 2 slot 25 which is formed in the upper part 21v of the link 19. The bushing 24: supports the link and-pawl-and is loosely mounted upon the crank 3. An aperture 26 is formed in the end27 of the pawl 19, to provide a bearing for the stud shaft 8 of the head 6. The .pawl v20 is provided with fingers 28 and 29,

which extend xmtwardly therefrom as showin .When movement is imparted to the dl'lVv I ing shaft 1 the crank 3 imparts a combined reciprocating and oscillating movement to the pawl and link both of which latter in turn transmit a reciprocating movement-to the head 6. After the crank 3 has traveled .to within about of an inch of. the end of its downward stroke the pawl is forced to engage with the abutment or shoulder 22of the link, (as shown in the fulllines :2) by the tension of the in Fig; spring 30 which is fastened to the link 21 by the screw 31. The

' end of thespr'ing exerts tension on av screw 9 33 which is secured to the pawl-20, a stop 34:

being prdvided to prevent the pawl from moving outof engagementwith the abut-- ment. 22 ofthe l nk. 1 Y 2 The finger 28 and cam 16 arearranged so before the work that when the finger in upstroke, reaches the point 35 of the cam 16' the pawl and link are within 1; of an inch of the end of their up stroke. When the finger 28 contactswith position shown in dotted lines in Fig. 2.

Upon the finger 28 reaching the end 35 of the cam face 16 the finger 29 is then in contact with the end 36 of the cam 15, thereby keeping the pawl in released position until When the finger 29 reaches the point 37- on the cam 15 the pawl' and link are within the finger 29 reaches the point 37 on the cam 15.

. of an inch ofthe end of their downward stroke and the follower or work engaging element is within of an inchof the anvil, preparatory to completing its downward movement to act upon the work.

- As soon as thefinger-29 reaches the point 37 ofthe cam 15 it disengages therefrom, as the throw of the crank 3.carries the finger 29 awayfrom the cam 15 which permits the sprlng 30 to exert its tension upon the end of the pawl, forcing the latter into-locked pos tion, or in contact with the abutment 22 to thereby couple the work ment to the driving means: I

, The pawl is. engaged with the link just engaging element reaches the end of its downward stroke to act upon the work and continues to be engaged. therewith until the finger, 28 of the pawl again reaches the point 35 of the cam 16 in its upward stroke. The-cams are arranged and secured to the holder so that the finger-28 will contact with the point 35 when the pawl is within of an inch of its upward stroke.

tion of the driving shaft 1. p a It will be noted that the link and pawl are not locked together during the major part of the downward stroke pf the working element, but only during the final part of such stroke. If an obstruction, as for instance the finger 38, of the operator, jected between the work engagmg element 17 and the anvil 18, whichfi'nger is in thickness in excess of g of alrinch, the downward stroke of the head will be arrested and the head and link will idle, the crank 3 completing its strokejby passing or moving, withbushing 24,, through theslot 25, since the end 23 of the pawl20 cannot contact with the abutment or shoulder 22 as shown in the dotted lines in Fig. 1 owing to its being in a position where it cannot engage shoulder 22 This operation is repeatedupon each, revolutherefore no pressure can be exerted upon the obstruction. v

It will be noted, that by the aforementioned cam action, thepawl isout of operaengaging eleis interposed or protive connection with or is released from connection with the link during the'ma3or portion of its downward stroke and is only permitted to be locked to or engaged with can be used to operate the pawl, the arrangement as shown in the drawings being especially suitable for the conventional type of staying machines now in use.

, In case the spring becomes disarranged or' I broken the pawl cannot interlock with the link and the link and pawl are thus maintained positively disconnected or released from'each other during the major portion" of the downward stroke as stated above, whether the spring is performing its function or not.

It will further be noted that the pawl and link virtually form, or constitute a breakable joint incorporated in a connection, which the pawl and link form, between the work ,engaging element and the reciprocating means, which joint isnormally broken and only is made or completed, when no obstruction engages the element, or in other words, when there is free space between the anvil and element. r

i What is claimed is: 1. In combination with a work engaging element and a driver, amulti-part breakable connection between the element and driving means to actuate the former from the latter, automatic stationary cam means to normally maintainsaid connection broken, and automatic means for causing the connection to be made when there is free space between the anvil and element.

2. The combination with a work-performingelement and a driving element therefor,

of means for'actuating the former from the latter, comprising a linlg and a pawl and stationary cam means for controlling the engagement of the pawl with the link.

3. The combination with a work-perform- .ing element and a driving element therefor,

of yieldable means for actuating the former from the latter, and stationary cam .means associated with the driving element for. controlling the operation of the' yieldable means.

4. The combination with a work performing element and a driving element therefor, of a link extending between the same and having sliding connection with one of said elements; a' pawl mounted on one of said elements and adapted to engage the link, and a stationary cam arranged to engage the pawl to prevent such engagement when the path of the work performing element to the work is obstructed.

5. In a machine having a work engaging element and an anvil, driving means for reciprocating said element comprising a link and a pawl, said link being a one-piece member connected at" its opposite ends with the work-engaging element andthe driving means respectively, and stationary cam means to automatically actuate, the pawl to renderthe work engaging element in-' operative to prevent the element from engaging with the anvil when an obstruction extraneous to the work is located in the path a of movement of the work-engaging element.

6. In a machine having a work engaging element and an anvil, mans for reciprocating said element to exert pressure upon the anvil comprising an intenlocking link and, pawl, and a stationary cam to automatically and positively unlock the pawl from the link to render the work engaging. element inoperative.

7. In a machine having a workengaging element and ananvil, means for reciprocating said element to exert pressure upon the anvil comprising an interlocking link and pawl, a stationary cam to automatically and positively unlock the pawl from the link to render the workengaging element inoperative, and means to automatically lock the pawl-and link just-prior to the engagement of the work by the work-performing element.

8. In combination with a driving means,

a reciprocating workeengaging element,

means comprising a full link and-a pawl to connect said driving means and element, 7

ing at its opposite ends to the driving means .and work engaging means respectively, means to automatically lock said link and pawl to exert a working action upon the work-engaging element at a predetermined point, and stationary cam means to automatically unlock the link and pawl at a pre determined point.

9. In a machinehaving a'reciprocating work-engaging element and an anvil, driving said link being a one-piece member connectthere is a free space between the elementand the anvil and a stationary cam to automatically and positively prevent the-making of the' joint when I obstruction extraneousto the work.

'11. In combination with an anvil, a workengagmgelement, driving means therefor,

a multi-part breakable and slidable connection between 'the element and-driving means I to a'ctuatethe element, stationary cam means 'fautomatically operative to normallyma'in tain said connection broken, said connection embodying acne-piece link operatively con-" nected at its opposite ends with the driving tion when there is free space between the means and'work-engaging element respectively, and automatic means to make connec anvil and work. I 4

12; In combination with a work engaging element, and a driver therefor, a multlpart breakable connection between the ele- 9 ment and driving means to actuate the former from the latter, and'automatic stationmeans and element, and means to allow the 1 .30

- and toexert pressure upon-the wor connection broken. I r

13. In a safety device. for a machine ary cam means tonormally maintain said equipped with a work-engaging element, and

drlving means, means. to couple the driving coupling means to yield when an obstruction is encountered in its path before it reaches a predetermined point in its Working the element encounters an,

stroke, engag ing element at a predetermined point in its working stroke. including a stationary cam couphng means inoperative. v v

with a work-engaging element, a driver and ananvil, a normally uncoupled connection for driving the element from the. driver, and

14. In a' safety device, in combination mally maintaining said connection un coupled and for allowing coupling thereof when the pathofthe element to the anvil is work. I

tionary cam' plate arranged to prevent pressure frombeing exerted on the workengaging means upon said means being subjected to pressure before it reaches said predetermlned point' in its working stroke.

Intestimony whereof I aflix my signature in presence of two witnesses.

Witnesses: v

JOHN H. Coss,- PEARL A. YUNCHER1:

CHARLES E: ROOTJ plate operative" to normallymaintain the 1 means including a stationary cam for nor 45 free of any obstruction extraneous to; the 

